Transformer-tank breather.



A. HUNDT.

TRANSFORMER TANK BREATHER..

APPLICATION FILED 001'. 29; 1912.

Patented June 28, 1914.

WfTNE'SE-ES. INYENTUH JTLBEHT Hzuvum, W @m .His ATTURNELY.

UNITED- STATES FATE QFFICE.

ALBERT HUNDT, OF PANKOW, GERMANY, ASSIGNOR T0 GENERAL ELECTRIG COMPANY,

A CORPORATIGN OF NEW YORK.

TRANSFORMER-TANK BREATHER.

Specification of Letters Patent;

Patented June as, 1914.

Application filed'october 29, 1912.- Serial No. 728,446.. Y

the oil must be kept as dry as possible since the addition thereto of even a small quantity of moisture considerably reduces its electrical insulating qualities, and the insulating qualities of the insulating materials of the transformer proper are likewise liable to suffer.

A transformer case. cannot generally be made absolutely air tight because the materials within the tank change appreciably in volume as the load on the transformer increases or decreases; this then requires that there be some connection between the interior of the tank and the atmosphere to.

allow the equalization of the pressures within and without. Entering air from the surrounding atmosphere tends to convey moisbreather.

One object of my invention is to increase the period ofeflectiveness of the moisture removlng means within the breather by reuirin it to act onl on air sin between l g y f o contact with the atmosphere and required the exterior and the interior of th tank. I propose to do this by providing a valve means, which may assume any one of numerous form's, located in the passage between the moisture removing means and the atmosphere, this valve means closing this passage when the pressures within and without the tank are substantially equal. llhe moisture removing means is thus kept from to act on little air other than that actually passing between the interior and the exterior of the tank.

The accompanying drawings illustrate diagrammatically two constructions involving my invention.

F igu-re 1 is a sectional; elevation of a construction involving my invention wherein the port is normally closed by oil. Fig. 2 is also a sectional elevation wherein a double acting valve is provided.

In Fig. l thechamber 1 of the breather is shown opening into the interior of the transformer tank 2 which is nearly filled with oil- Upwardly. from the bottom of the chamber 1 extends a portion 3 provided through its center with the port to atmosphere.

Into the annular portion of the chamber 1 thus formed extends a fixed bellshaped member 4 as shown. This bell may,

be held in position by means of the per forated annular ring 5. Above the annular ring 5 is placed the moisture removing means, the vessel 6 containing a hygroscopic material, such for example, as chlorid of potassium. The lower edge of the hell 4 is submerged in oil in the annular bottom of the chamber 1. As the pressure in the interior of the tank rises above orfalls below the pressure of the atmosphere, air will be forced out under the edge of the hell 4; and through the passage'3, or will be drawn in through the passage 3 and under the edge of the hell 4. When the pressures Within and without the tank equalize, the oil assumes a position somewhat similar to that shown in Fig. 1, thus efiectively' sealing the interior of the chamber 1 from the atmosphere. Very little air therefore, comes in contact with the moisture removing meansof the vessel 6 except that actually passing into 'or from the tank 2. It is obvious that the length of time the moisture removing means may be allowedv to go without attention depends upon the quantity of air it is forced to act upon. By my invention the quantity of air upon which it is required to operate is reduced to a minimum, to but little more than the quantity actually entering and leaving the interior of the transformer tank.

' Another construction involving my invention is shown in Fig. 2. In this construction the moisture removing means 6 is likewise located in the chamber 1 above a perforated plate 5. Below this plate is a valve 7 which is capable of moving on the rod 8 both into and out of the chamber 1. Above and below the valve 7 are springs 9 andlO respectively. When the pressure within the tank falls below that of the atmosphere, the valve 7 is forced upward against the spring 9 and air from the atmosphere enters the tank through the chamber 1, being deprived of its moisture by the moisture removing means 6. When on the other hand the pressure within the tank exceeds that of the atmosphere, the valve 7 is moved downward against the spring 10, and air. passes from the tank. Whenever the pressures equalize, the valve 7 assumes the mid position shown wherein the passageway between the chamber 1 and the atmosphere is closed.

What I claim as new and desire to secure by Letters Patent of the United States, is:

phere to said device on the substantial equali- I zation of the pressures within and without the tank.

2. The combination with a transformer tank, a vessel connected with the interior thereof and provided with a port to the atmosphere, moisture removing means within the vessel and means for closing said port on the substantial equalization 'of the pressures within and without the tank.

3. The combination with a transformer tank, a vessel connected with the interior thereof and provided with a port to the atmosphere, moisture removing means within the vessel and valve means automatically closing said port on the substantial equalization of the pressures within and without the tank.

In witness whereof, I have hereunto set my hand this 14th day of October, 1912.

ALBERT HUN DT.

Witnesses:

EDMUND FENDER, AMo KARREN. 

